Incandescent electric lamp



(No Model) v 3 T. E. GATEHOUSE. INGANDESGENT ELECTRIC LAMP.

No. 284,409. Patented Sept. 4 1883.

Invnom QaZeZom Unites STA-res TOM ERNEST GATEHOUSE, F CAMBER'WELL, COUNTY OF SURREY, ENGLAND.

lNCANDE3i3ENT ELECTRIC LAME.

SPEGIFIGJLTiON forming part of Letters Patent No. 284,409, dated September 4:, 1883.

Application filed November 9, 1882. (No model.) Patented in England July 25.

Austria April 8, 1882, No. 4,524; in New South. Wa-lesJune 28,1882,

No. 147,003,- in Belgium Jannaryzfi, 1882, No, 56,887; in

1881, No. 3,240,- in France January 24, 1882,

No. 7,332; in Italy June 30. 1882, XX'Vl'il- 418; in Sweden July 15, 1882; in India August 14, 1882, No. 840; and in Norway September 2, 188:2.

To all whom, it may concern:

Be it known that 1, Ton: ERNEST Gurn- HOUSE, a citizen of England, residing at Gamberwell, in th e'county ol'Surir-y, Ei'igl an d, have I-n8, 1882; Italy, v01. XXV,

invented an Improvement in Incandescent Electric Lamps, (for which I have obtained patents in Great Britain, No. 3,240, dated. July 25, 1881; France, No. 14'7,003,-dated Jannary 24,- 1882; Belgium, No. 56,887, dated January 25, 1882, Austria, No. 4,524., dated II, No. 118, dated June 80, 1882; Sweden, 'da July 15, 1882; Norway, dated September 2,'1S82; India, No. 840, dated August 14., 1882; and New South WVales, No. 7,332,.datcd June 28, 1882,) of which the following is a specification.

In incandescent electric lamps, when a fine platinum or other metallic wire is employed as the illuminant, there is danger of its fusion or destruction by excess of current.

My invention relates to means of guarding against this risk by employing, in combination with the illuminant-wire, a conductor, forming with'it a parallel circuit, this conwire. Such a dnctor being in. respect of electri cal resistance relatively to heat of a character opposite to the substance is carbon, for, while the resistance of a metallic wire increases with increase of temperature, the resistance of a rod im ention.

or filament of carbon decreases with increase of temperature. Taking advantage of this property, 1 divide the electrical cir init of the lamp into two parallel branches, one through the wire and the other through a rod or iilament of carbon, and thus, if the current should increase, heating both wire and carbon, a smaller portion of the increased current will the platinum wire 1 incandescent lamps, with their two parallel circuits invariable. Fig. i is an. elevation,.-

and 5 and 6 are part transverse sections,

of a lamp, in which the carbon circuit can be crease or diminish the ion gth oi'carbon through which part ofthe c rrent passes, the other part passing through I; \VNV are the conduct ing-wires t0 and from the lamp. In Fig. 2 and a carbon filament, (l, are both fixed. side by sidewithiu an exhausted globe, G. In Fi the pl mum wire P is in an inner globe, which may be open at the bottom, and the carbon. filament O isinclosed in an exhausted space bQlLVVOGll. the inner globe and the outer globe, (i. In Figs. 4: and 5 the platinum wire P is within the carbon rod 0 is fixed within the standard of the lamp, the length oi. the carbon circuit being varied by an insulated rubber or brush, S, that can he slid up or down the carbon by hand applied. to an exteriml button. In 6 the carbon C has the form of a circular are,

along which a contact brush or spring, S, "11

be moved by turning a button.

in the self-regulating arrangement shown in Fig. 7, M is a solenoid having its coil. in the circuit oi'the'lamp, and attracting, in opposition to aspring, its iron core I, which carries contact-rollers S, embracing a carbon rod, 0.

'ihe platinum wire .P may be placed, as

a globe, and

shown, within an inner globe, which is supported on flexible wire springs E within a larger globe, so that the platinum is ed from shocks when the lamp is moved about.

I am aware thatgin an incandesci 11g electric lampa material which is normally anon-co ductor has been arranged to become a con-.

doctor and form a part of a branch circuit parallel with the incandesciug filament when heated by said :lilamentfiind I do not claim. such a lamp.

Having thus described the nature of my in r 5 stance,

25 ity while subject to the by any excess of current is received by the eon- 2 esaaec vention, and. the best means I know of putting itin practice, I clai 1. In an incandescing electric lamp, two normally-conducting materials-such, for in as platinum and carbon-having such property that the electrical resistance of the one increases and'that of the other decreases with the elevation of the temperature, and

combined, substantially as set forth, in parallel circuit, whereby any excess of current is received by the carbon conductor, as described.

2. In an incandescing electric lamp, the combination, with an incandescing filament or burner having; the property that its electrical resistance increases with elevation of tempera-- ture, of a normal conductor arranged in par- ,allel circuit therewith, and having the prop -erty that its electrical resistance decreases with elevation of temperature, substantially as dcscribed.

3. In an incandescing electric lamp, the combination,with an incandescing 'fil ament, of a second conductor in parallel. circuit therewith,

both conductors being of different conductivsaine current, where l circuit therewith both conductors being of different conductivity while subj set to the same current, whereby any excess of currents is received by the conductor having increased conductivity under increase of temperature, and an adjustable device for regulating; the normal resistance of said. second conductor, for the purpose specified.

Intestimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 20th day of October, A. D. 1882.

TOM ERNEST GATEHOUSF.

Witncsscs:

Cir ,s. R. Gairsiiousn, J'No. P. M. MrLLAnn. 

